From an early age, organisms display variation in patterns of behavioral and physiological reactivity, temperament, emotionality, and personality, a set of overlapping constructs referred to as biobehavioral organization. These patterns appear early in life and are remarkably stable over time. A growing literature, has focused on the origins of this variation as well as its consequences for a variety of health outcomes. Such an individualized approach is evident in development of the field of personalized medicine, and this approach is becoming increasingly adopted in more applied settings as well, including in the management of captive nonhuman primates. At the California National Primate Research Center we have developed a BioBehavioral Assessment (BBA) Program to characterize biobehavioral organization in infant rhesus monkeys. The BBA Program involves a highly standardized, 25-hour-long, protocol that includes a) collecting behavioral data to assess memory, responsiveness to mild challenges, and willingness to interact with novel objects; b) genotyping for polymorphisms in the promoter regions of the serotonin transporter and monoamine oxidase-A genes; c) assessing regulation of the hypothalamic-pituitary-adrenal system; and d) measuring routine hematologic parameters. In addition to providing a database for scientific studies, the BBA Program contributes to the knowledge and improvement of the nonhuman primate resource at our own center, and published studies provide important information to management staff at other primate facilities in the United States as well. The following four specific aims are proposed: 1. Continue performing the BioBehavioral Assessment, and make these data available to management staff at CNPRC and qualified scientific staff at CNPRC and other institutions; 2. Incorporate into the BBA program a biomarker of inflammation, namely C-reactive protein, and examine the relationship between this marker and other BBA measures, as well as health outcomes; 3. Continue to examine causes and consequences of variation in BBA measures to better understand how biobehavioral organization is affected by management procedures, and to determine whether biobehavioral organization predicts abnormal behavior outcomes; 4. Improve dissemination of important colony management-related findings via both inreach efforts (focusing on education and training of individuals at CNPRC), and outreach efforts (for the larger nonhuman primate behavior management community).